Much of Africa is experiencing a dramatic epidemiological transition driven in opposite directions by continuing improvements in the management of traditional infectious diseases, concurrent exploding HIV and TB epidemics, the continuing impact of malaria, and swift increases in the prevalence of chronic non- communicable diseases. Tragically there are very few representative, reliable data to illuminate these remarkable changes, or more importantly to guide the design and measure the effects of interventions aimed at improving the situation. A rapidly growing group of demographic surveillance system (DSS) sites is collecting valuable population-based, longitudinal data describing both the health and social dimensions of this epidemiological transition, and many of the roughly twenty DSS sites in Africa also conduct population-based health intervention testing and drugs trials. This data-archiving and data-use project fits into a long-term plan of the INDEPTH Network of DSS sites which has the overall goal of making the unique and valuable health and population data generated by DSS sites widely available and representative of larger populations that are more relevant to designing interventions and formulating policy. Together with an ongoing pilot of identical physical and cognitive function modules in several African and Asian DSS sites, this project contributes to the foundation of an envisaged multi-site study of adult health and aging in Africa. The specific aims of this project are to develop, prototype and pilot: 1) standards for the definition and management of DSS data, 2) policy, procedures and technology to make the data from one or more DSS sites widely available, 3) standardized, automated routines to calculate commonly used indices, rates and measures relating to longitudinal population data, 4) database designs and GIS tools to fully integrate health and demographic data with spatial and geographic information, and 5) methods to manage concurrent paper and electronic archives of DSS data. The Agincourt Demographic and Health Surveillance system site in South Africa has volunteered itself for this pilot project and is committed to providing access to its data at the end of the project using tools developed by the project and under the policies formulated as part of the project. Additional outcomes of this project will include: 1) piloted prototypes of the technology, tools, policies and procedures necessary to widely disseminate DSS data; 2) prototype routines to calculate standard measures from DSS data; 3) designs and tools to fully integrate DSS and geographic information; and 4) tools to tightly coordinate the management of concurrent paper and electronic archives of DSS data. [unreadable] [unreadable] [unreadable] [unreadable]